Yeah, but for this one in particular, for example any kid who know a little bit about physic has try this in front of other who doesn't At least i did, so yeah he put it on a big ring/hoop. Does someone doing a trick with a tux are doing a new trick ? aaahhh big question...
What the problem actually does he steal contract or money from someone else ? Maybe he doesn't quote the well know original creater of the trick ?
Does he do art ? no he do comedy, so you have to question the fact that joke are copyright or copyleft, same for juggling trick.
If you don't know, go try to copyright a trick of you or a joke, maybe you can do it for a act.